Simple buzzer parking sensor with 4 sensors 
Model No.: CT336-4
  
Features and Functions

Alarm by three step Bi-Bi sound;
Full-weather design, un-affected by awful weather                                 
All kinds of sensor colors and styles are available                                 
Easy to install  
Measuring the distance by radar
sensors optional:
   2 rear
   4 rear
   4 rear + 2 front
   4 rear + 4 front
Up to 50 sensor colors available(Black,silver,white,grey,red,etc.)    
Easy to fit,DIY installation 
 
Technical Parameters

Operating voltage rating: DC12V.
Max power: Pmax<5W.
Operating temperature: -40℃~80℃.
Alarm Distance: 0.1m~1.5m.                                                                                       Alarm voice: >80dB.
Ultrasonic frequency: 40KHz.